Effect of sialyllactose administration on growth performance and intestinal epithelium development in suckling piglets

Zinc Oxide Administration Relieves the Diarrhea of ETEC K88-Infected Piglets by Reducing Ileal Apoptosis and Maintaining Gut Microbial Balance

The impact of ZnO as a feed additive on growth-performance and intestinal function of Enterotoxigenic Escherichia coli (ETEC) K88-infected piglets remains unclear. Fecal scores of piglets in ETEC group were significantly increased compared to control group. ETEC K88 significantly damages the small intestine, including a reduction in villus height in the jejunum, duodenum, and ileum, and a decrease in total superoxide dismutase activity in the jejunum and catalase activity in the ileum and jejunum. Compared to control group, ETEC K88 infection significantly elevated the mRNA level of gene IL-1β and the level of ileal epithelial cell apoptosis. ZnO administration significantly alleviated these negative effects and improved the antioxidative capability of the ileum. Moreover, ZnO supplementation alleviated the imbalance of gut microbiota by restoring the reduced amount of Enterococcus and Lactobacillus in the jejunum, Clostridium in the ileum, and Lactobacillus in the cecum, as well as the increased amount of total eubacteria in the ileum and Enterococcus in the cecum induced by the ETEC K88 infection. In conclusion, ZnO administration can reduce the diarrhea of piglets infected with ETEC K88 by reducing the structural damage of the intestine, attenuating intestinal oxidative stress and epithelial cell apoptosis, and modulating the gut microbiota.

The Role of Milk Oligosaccharides in Enhancing Intestinal Microbiota, Intestinal Integrity, and Immune Function in Pigs: A Comparative Review

The objective of this review was to identify the characteristics and functional roles of milk coproducts from human, bovine, and porcine sources and their impacts on the intestinal microbiota and intestinal immunity of suckling and nursery pigs. Modern pig production weans piglets at 3 to 4 weeks of age, which is earlier than pigs would naturally be weaned outside of artificial rearing. As a result, the immature intestines of suckling and nursery pigs face many challenges associated with intestinal dysbiosis, which can be caused by weaning stress or the colonization of the intestines by enteric pathogens. Milk oligosaccharides are found in sow milk and function as a prebiotic in the intestines of pigs as they cannot be degraded by mammalian enzymes and are thus utilized by intestinal microbial populations. The consumption of milk oligosaccharides during suckling and through the nursery phase can provide benefits to young pigs by encouraging the proliferation of beneficial microbial populations, preventing pathogen adhesion to enterocytes, and through directly modulating immune responses. Therefore, this review aims to summarize the specific functional components of milk oligosaccharides from human, bovine, and porcine sources, and identify potential strategies to utilize milk oligosaccharides to benefit young pigs through the suckling and nursery periods.

A FRET based ultrasensitive fluorescent aptasensor for 6'-sialyllactose detection

As a kind of human milk oligosaccharide, 6'-sialyllactose (6'-SL) plays an important role in promoting infant brain development and improving infant immunity. The content of 6'-SL in infant formula milk powder is thus one of the important nutritional indexes. Since the lacking of efficient and rapid detection methods for 6'-SL, it is of great significance to develop specific recognition elements and establish fast and sensitive detection methods for 6'-SL. Herein, using 6'-SL specific aptamer as the recognition element, catalytic hairpin assembly as the signal amplification technology and quantum dots as the signal label, a fluorescence biosensor based on fluorescence resonance energy transfer (FRET) was constructed for ultra-sensitive detection of 6'-SL. The detection limit of this FRET-based fluorescent biosensor is 0.3 nM, and it has some outstanding characteristics such as high signal-to-noise ratio, low time-consuming, simplicity and high efficiency in the actual sample detection. Therefore, it has broad application prospect in 6'-SL detection.

Bacillus coagulans prevents the decline in average daily feed intake in young piglets infected with enterotoxigenic Escherichia coli K88 by reducing intestinal injury and regulating the gut microbiota

Background

Enterotoxigenic Escherichia coli (ETEC), an important intestinal pathogen, poses a significant threat to the intestinal health of piglets. Bacillus coagulans (BC), a potential feed additive, can improve the intestinal function of piglets. However, the effects of BC on growth performance and intestinal function in ETEC-infected piglets are still unclear. In this study, 24 7-day-old piglets were randomly assigned to three treatment groups: control group (fed a basal diet), ETEC group (fed a basal diet and challenged with ETEC K88) and BC+ETEC group (fed a basal diet, orally administered BC, challenged with ETEC K88). During Days 1-6 of the trial, piglets in the BC+ETEC group were orally administered BC (1×108CFU/kg). On Day 5 of the trial, piglets in the ETEC and BC+ETEC groups were orally administered ETEC K88 (5×109CFU/piglet). Blood, intestinal tissue, and content samples were collected from the piglets on Day 7 of the trial.

Results

The average daily feed intake in the ETEC group was significantly reduced compared to that of the control group. Further research revealed that ETEC infection significantly damaged the structure of the small intestine. Compared to the control group, the villus height and surface area of the jejunum, the ratio of villus height to crypt depth in the duodenum and jejunum, and the activities of catalase and total superoxide dismutase in the jejunum were significantly reduced. Additionally, the levels of myeloperoxidase in the jejunum, malondialdehyde in the plasma and jejunum, and intestinal epithelial apoptosis were significantly increased in the ETEC group. However, BC supplementation had significantly mitigated these negative effects in the BC+ETEC group by Day 7 of the trial. Moreover, BC supplementation improved the gut microbiota imbalance by reversing the decreased numbers of Enterococcus, Clostridium and Lactobacillus in jejunum and Escherichia coli, Bifidobacterium and Lactobacillus in the colon, as well as the increased number of Escherichia coli in the jejunum induced by ETEC K88.

Conclusions

Overall, BC supplementation reduced the decline in average daily feed intake in ETEC K88-infected piglets by attenuating intestinal epithelial apoptosis and oxidative stress and regulating the gut microbiota. This suggests that BC may be used to prevent intestinal infections caused by ETEC in piglets.

Protective effect of sialyllactose on the intestinal epithelium in weaned pigs upon enterotoxigenic Escherichia coli challenge

Sialyllactose (SL), one of the most abundant oligosaccharides present in porcine breast milk, has been implicated in many biological functions, including the prebiotic and immune-modulating effects. This study was conducted to investigate the influences of dietary SL supplementation on intestinal barrier functions exposure to enterotoxigenic Escherichia coli (ETEC) in a porcine model. Thirty-two pigs were assigned to four treatments, fed with basal or SL-containing (5.0 g kg-1) diet, and orally infused with ETEC or culture medium. SL supplementation significantly reduced the diarrhea incidence and the abundance of E. coli in feces (P < 0.05). Interestingly, SL attenuated ETEC-induced intestinal epithelium injury as indicated by the decreased serum concentrations of diamine oxidase (DAO) and D-lactate and reduced the number of apoptotic cells in the jejunal epithelium (P < 0.05). Moreover, SL not only elevated the abundance of the tight-junction protein ZO-1 in the duodenal and ileal epithelium but also elevated the antioxidant capacity and the number of SIgA positive cells in the jejunal epithelium upon the ETEC challenge (P < 0.05). Importantly, SL decreased the expression levels of inflammation-related genes such as the tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), myeloid differentiation factor 88 (MyD88) in the duodenum, and ileum upon ETEC challenge (P < 0.05). SL also significantly elevated the expression levels of two critical antioxidant genes such as the nuclear factor erythroid-2 related factor 2 (Nrf-2) and kelch-like ECH-associated protein 1 (KEAP-1) in the jejunum (P < 0.05). These results suggested that SL can alleviate ETEC-induced intestinal epithelium injury, which is associated with suppressed inflammation, improved intestinal immunity, antioxidant capacity, and improved intestinal epithelial functions.